public void testInputFormat() { try { JobConf conf = new JobConf(); String TMP_DIR = System.getProperty("test.build.data", "/tmp"); Path filename = new Path("file:///" + TMP_DIR + "/tmpSeqFile"); SequenceFile.Writer sfw = SequenceFile.createWriter( FileSystem.getLocal(conf), conf, filename, ChukwaArchiveKey.class, ChunkImpl.class, SequenceFile.CompressionType.NONE, Reporter.NULL); StringBuilder buf = new StringBuilder(); int offsets[] = new int[lines.length]; for (int i = 0; i < lines.length; ++i) { buf.append(lines[i]); buf.append("\n"); offsets[i] = buf.length() - 1; } ChukwaArchiveKey key = new ChukwaArchiveKey(0, "datatype", "sname", 0); ChunkImpl val = new ChunkImpl("datatype", "sname", 0, buf.toString().getBytes(), null); val.setRecordOffsets(offsets); sfw.append(key, val); sfw.append(key, val); // write it twice sfw.close(); long len = FileSystem.getLocal(conf).getFileStatus(filename).getLen(); InputSplit split = new FileSplit(filename, 0, len, (String[]) null); ChukwaInputFormat in = new ChukwaInputFormat(); RecordReader<LongWritable, Text> r = in.getRecordReader(split, conf, Reporter.NULL); LongWritable l = r.createKey(); Text line = r.createValue(); for (int i = 0; i < lines.length * 2; ++i) { boolean succeeded = r.next(l, line); assertTrue(succeeded); assertEquals(i, l.get()); assertEquals(lines[i % lines.length], line.toString()); System.out.println("read line: " + l.get() + " " + line); } boolean succeeded = r.next(l, line); assertFalse(succeeded); } catch (IOException e) { e.printStackTrace(); fail("IO exception " + e); } }
/** * Produce splits such that each is no greater than the quotient of the total size and the * number of splits requested. * * @param job The handle to the JobConf object * @param numSplits Number of splits requested */ public InputSplit[] getSplits(JobConf job, int numSplits) throws IOException { int cnfiles = job.getInt(SRC_COUNT_LABEL, -1); long cbsize = job.getLong(TOTAL_SIZE_LABEL, -1); String srcfilelist = job.get(SRC_LIST_LABEL, ""); if (cnfiles < 0 || cbsize < 0 || "".equals(srcfilelist)) { throw new RuntimeException( "Invalid metadata: #files(" + cnfiles + ") total_size(" + cbsize + ") listuri(" + srcfilelist + ")"); } Path src = new Path(srcfilelist); FileSystem fs = src.getFileSystem(job); FileStatus srcst = fs.getFileStatus(src); ArrayList<FileSplit> splits = new ArrayList<FileSplit>(numSplits); LongWritable key = new LongWritable(); FilePair value = new FilePair(); final long targetsize = cbsize / numSplits; long pos = 0L; long last = 0L; long acc = 0L; long cbrem = srcst.getLen(); SequenceFile.Reader sl = null; try { sl = new SequenceFile.Reader(fs, src, job); for (; sl.next(key, value); last = sl.getPosition()) { // if adding this split would put this split past the target size, // cut the last split and put this next file in the next split. if (acc + key.get() > targetsize && acc != 0) { long splitsize = last - pos; splits.add(new FileSplit(src, pos, splitsize, (String[]) null)); cbrem -= splitsize; pos = last; acc = 0L; } acc += key.get(); } } finally { checkAndClose(sl); } if (cbrem != 0) { splits.add(new FileSplit(src, pos, cbrem, (String[]) null)); } return splits.toArray(new FileSplit[splits.size()]); }